Cut-off valve for steam engines



B. F. QBRYANT CUT-OFF VALVE FOR STEAM ENGINES Original Filed May 1921May 26,1925.

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l TTUHNEYS WITNESSES W Patented May 26, 1925.

UNITED STATES PATENT OFFICE.

BENJAMIN F. OBRYANT, OF GADSDEN, ALABAMA, ASSIGNOR OI ONE-HALF TO I. M.

ROSEN, F GADSDEN, ALABAMA. I

CUT-DEF VALVE FOR STEAM ENGINES.

Application filed May 12, 1921, Serial No. 468,905. Renewed March 30,1925.

T 0 (1H whom it may concern:

Be it known that I, BENJAMIN F. OBRYANT, a citizen of the United States,and a resident of Gadsden, in the county of Etowah and State of Alabama,have in vented certain new and useful Improvements in Cut-Off Valves forSteam Engines, of which the following is a specification.

This invention relates to cut-off valves for steam engines.

' ward head of one of the cylinders to b blown out or in some mannerknocked off; When this condition arises it has been the practice to lockor block the valve controlling the entry of steam to the cylinder insuch a position that any possibility of steam escaping into the cylinderis eliminated. The operating means for the valve is also'at the sametime disconnected and thus rendering the entire cylinder inoperative. Insome cases the engine may proceed by operating with one cylinder. Itoften happens however, that when the forward head is blown from one ofthe cylinders, that the piston of the other cylinder is at a point ofdead center. In an instance of this kind, the engine becomes entirelyout of commission in that the piston within the cylinder which has notbeen broken cannot be started.

With the above in view, it is the object of the present invention toprovide a valve by which the admission of steam into the forward end ofa cylinder of the above mentioned character may be stopped with outimpairing the normal operation of the controlling valve and therebypermit a piston within a cylinder having its forward head broken away tocontinue to make a forward power stroke. This is of great value in casethe other piston is on dead center in that the forward stroke would besufiicient to start the engine and move the other piston off of deadcenter thus enabling the same to start. The engine may then continue toproceed upon its way, the piston in the broken cylinder operating in theusual manner but only transmitting power during its forward stroke.

The invention is illustrated by way of example in the accompanyingdrawings, in Which- Figure 1 is a vertical central sectional view ofthecylinder, steam chest and valve operating mechanism as commonlyemployed on the one side of a railroad locomotive,

Figure 2 is a vertical section taken substantially on the lines 2-2 ofFigure 1, and

Figure 3 isia detail perspective view of the cut-off valve.

Referring to the drawings more particularly, indicates generally acylinder of the type heretofore referred to, 11 the for-. ward headthereof, and 12 the rearward head. On top of the cylinder there isformed the usual steam chest 13 which is formed with the extended hollowportions 14- and 15, said portions beingin alinement with each other andeach adapted to slidingly accommodate one of the heads of the doubleheaded valve member 16. The steam chest and cylinder together with theirassociated parts are carried by the body of the engine through the meansof the extension 17, Figure 2, and the plates 18 as shown in Figure 1. i

The cylinder '10 is provided with the usual piston 19. and said pistonbeing connected through the connecting rod 20 for actuating the drivewheels on one side of the engine; The wall 21 which extends between thesteam chest 13 and cylinder 10, is provided with the usual ducts 22, oneat each end thereof as shown; also the extensions 14 and 15 are eachprovided with an exhaust port as indicated at 24, and communicating withthe interior of the steam chest 13 is a steam supply pipe 26. Theoperation of the valve 16 for permitting steam to enter the ducts 22 andalso exhausting therefrom, so that the piston 19 will be reciprocatedwithin the cylinder 10 is well known and understood so that no detailedexplanation thereof need here be made.

In carrying out the present invention, I provide a bore 27 which istransverse to the duct 22 and preferably passing therethrough at thepoint shown. The bore 27 is adapted to accommodate the circular heads 28of the valve member 29. The portion 30 which connects the two circularhead members 28 of the valve member 29 has an inner surface whichcorresponds in curvathe object being that when the portion of the valverneniber is disposed as shown in light cross section lines in Figure 1,the same will not offer any interference to the flow of steam throughthe duct, but when disposed as shown in heavy cross section lines in thesame fi'gi'ir'e', said portion will form a tight closure against anyflow of steam through said duct. The outer end of the valve 29 iscovered by a cap 31, which is secured against removal by the means ofscrews as indicated at 32. The outer circular head of the valve memberis also forined with a square recess as indicated at 33; and 1nalineinent with sa d recess there is threaded into the head of the cap"31 a plug 34, said plug having a squared portion 35 to which a wrenchmay be applied for removing the same, a set screw 31" serving toadjustably hold the valve mernber 29.

In the use of the present invention, as-

- smiling that the engine with which the same is to be associated is thetwo-cylinder type, that is, a cylinder located on each side i of theengine, each cylinder would then be provided with a cut-off valve, thesame being located in the forward duct 22 in each instance Now in casethe forward head 11 would be blown from either of the cylinders thenitwould only be necessary to remove the plug 345 and by the use of asquare bar and wrench turn the valve member 29 so that the same will bedisposed as shown in Figure 1', and at which time the duct 22 would beopen. No steam can then escape from the steam chest 13 into the forwardend of the cylinder 10. The closing of the forward duct 22- wouldhowever in no way interfere with the operation of the valve 16, andtherefore the valve Ihay operate so that a forward power stroke of thepiston 19 may be; utilized. As before mentioned the fact that thisforward stroke of the piston 19 can be utilized as driving power is ofgreatiadvantage in case the piston of the other cylinder should happento be at dead center at the tiine when the cylinder head 11 was blownoff.

Also, it isto be noted that by the use of the present invention, in casea cylinder head is broken, that it takes but a few minutes to cut olfthesteam from the forward end of thecylinder impaired and perinit theengine to proceed. This a great saving of time when viewed with the oldpractice of blocking and disconnecting the controlling valve heretoforereferred to.

A Valve member removably mounted in a bore extending transversely of apassage, said passage and bore being formed in a body member and saidbore having its inner end closed, and said valve member comprising apair of "circular heads and a connecting portion therebetween adapted tobe utilized for controlling fluid flow through the passage, saidv valvenieinbe-r having one circular head slightly extending from the open endof bore, a cap fitted upon the last named end of the valve, a securingflange formed with the cap whereby the same may be secured to the bodymember, and a set screw threaded through a side wall of the cap wherebythe valve member may be adjustably held against rotation.

BENJAMIN F. OBRYANT.

